Bursaries designed to attract top graduates to teaching could deter those with qualifications in shortage subjects from working in primary schools, campaigners have warned.
Younger children will miss out on the skills of mathematicians and scientists because grants favour those who train to teach older pupils, the Government has been told.
Students will be entitled to far higher bursaries if they sign up to train as a secondary-school teacher than those on primary courses, under proposals set out by the Department for Education.
Trainee teachers with a degree in a shortage subject - science, maths, engineering and modern foreign languages - will be eligible for up to #163;20,000 if they sign up to a secondary PGCE. But the same graduates would only qualify for up to #163;9,000 if they opt for a primary PGCE under the changes to be introduced from September 2012.
Imran Khan, director of the Campaign for Science Education, said the bursary scheme would attract people into teaching who would otherwise have chosen different professions. But he has met education secretary Michael Gove and schools minister Nick Gibb to warn them about the implications of the policy for primary schools.
"It's strange because in other policies there is a strong focus on early years intervention, but this proposal about the bursaries gives the impression primary schools don't matter as much," he said.
"It wouldn't cost very much because so few maths graduates become primary-school teachers to begin with. It would be a small fraction of the cost of the bursaries overall.
"We have very few graduates in maths going into primary teaching, and hardly any physicists or chemists. This could make it worse. We need an even playing field, at least."
Annette Smith, chief executive of the Association for Science Education, has also highlighted the problem in her meetings with officials and ministers.
"I do understand the Department for Education is trying to do something big and quick to fix the problem of there not being enough physics and chemistry graduates going into teaching," she said. "After that they might think about primary schools.
"We are trying to draw attention to this, and to make them realise it's an important issue. We don't want scientists considering primary teaching swaying towards working in secondary school because there is a higher bursary."
SCORE, a collaboration of organisations - including the Royal Society and the Institute of Physics - have said primary trainees should be "entitled to the same level of support as those entering secondary initial teacher training courses (ITT)".
"There is a known shortage of Stem (science, technology, engineering and maths) graduates entering primary ITT and the strategy should reflect this," said chairman Professor Graham Hutchings in his response to the Government.
A DfE spokesman said: "We want to attract the best graduates to teaching and the training bursaries reflect the areas of greatest need."
In the 200910 academic year, just 10 people with physics degrees and 40 with chemistry degrees went on to train as primary-school teachers, according to figures from the Higher Education Statistics Agency.
Only 5 per cent of students on primary PGCE courses had a degree in maths or science.